Vent apparatus and method

ABSTRACT

A smart vent comprises a thermoelectric generator coupled to a power storage. The thermoelectric generator that generates voltage or electrical energy based on a temperature differential between a room temperature and a temperature in a duct where the smart vent is installed. The generator charges the storage using the generated voltage. A radio is coupled to the power storage and receives a wireless command from a device to open a vent so that air flows from the duct to the room. A processor, coupled to the storage and the radio, determines if there is sufficient charge in the power storage to open the vent apparatus; sends a command to a motor to open the vent if there is sufficient charge. A motor, coupled to the storage and processor, opens the vent upon receiving the command, thereby ceasing charging the power storage as the temperature differential decreases.

CROSS REFERENCE TO RELATED APPLICATIONS

This applications claims priority to and incorporates by reference U.S. Patent Applications No. 62/123,629 filed Nov. 24, 2014 by Hamid Najafi.

FIELD OF THE INVENTION

At least one embodiment of the present invention pertains to smart vents, and more particularly, to a smart vent apparatus with thermoelectric generator and related method.

BACKGROUND

A vast majority of homes and offices in the U.S. and many other countries use a “Forced Air” system for heating and cooling the interior of the building. In these systems, there is normally just one thermostat in one location and there are vents in each room for the air to flow through. This thermostat is the only control for the whole house temperature control.

If the door to a room is partially or completely closed or if the room is remote from the thermostat, the temperature in the room can differ significantly compared to the temperature of the thermostat. It can get either too hot or too cold depending on many variables like the size of the room, the size of the house, the location of the room, etc.

Also, there is no way for the occupants to set different temperatures for each room. For instance, parents might want to keep the children's bedroom(s) warmer than the master bedroom. Or the office room may not need to be heated at all during the night when vacant.

Accordingly, the lack of individual control for each area in the house makes the conventional system very inefficient both in terms of individual comfort and energy savings.

SUMMARY

This summary is provided to introduce in a simplified form certain concepts that are further described in the Detailed Description below and the drawings. This summary is not intended to identify essential features of the claimed subject matter or to limit the scope of the claimed subject matter.

In an embodiment, a smart vent comprises a thermoelectric generator coupled to a power storage. The thermoelectric generator that generates voltage or electrical energy based on a temperature differential between a room temperature and a temperature in a duct where the smart vent is installed. The generator charges the storage using the generated voltage. A radio is coupled to the power storage and receives a wireless command from a device to open a vent so that air flows from the duct to the room. A processor, coupled to the storage and the radio, determines if there is sufficient charge in the power storage to open the vent apparatus; sends a command to a motor to open the vent if there is sufficient charge. A motor, coupled to the storage and processor, opens the vent upon receiving the command, thereby ceasing charging the power storage as the temperature differential decreases.

In an embodiment, a method comprises: charging a power storage using a thermoelectric generator in a vent apparatus based on a temperature differential between a room temperature and a temperature in a duct where the vent apparatus is installed; receiving a command from a device to open the vent apparatus so that air flows from the duct to the room; determining if there is sufficient charge in the power storage to open the vent apparatus; opening the vent apparatus if there is sufficient charge; and cease charging the power storage when the temperature differential decreases.

Other aspects of the technique will be apparent from the accompanying figures and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the present invention are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements.

FIG. 1 is a block diagram illustrating a system.

FIG. 2 is a block diagram illustrating a smart vent of the system of FIG. 1.

FIG. 3 is a block diagram illustrating a controller of the smart vent of FIG. 2.

FIG. 4 is block diagram illustrating a memory of the controller of FIG. 3.

FIG. 5 is a block diagram illustrating a thermostat.

FIG. 6 is a flowchart illustrating a method of operating the smart vent of FIG. 2.

DETAILED DESCRIPTION

References in this description to “an embodiment”, “one embodiment”, or the like, mean that the particular feature, function, structure or characteristic being described is included in at least one embodiment of the present invention. Occurrences of such phrases in this specification do not necessarily all refer to the same embodiment. On the other hand, such references are not necessarily mutually exclusive either.

FIG. 1 is a block diagram illustrating a system 100. The system 100 is located within a room and comprises a smart vent 120 and a wireless thermostat 110 and/or smart phone 130 and/or other temperature control device. The wireless thermostat 110 talks to the vent 120 and commands it to close or to open so the temperature in the room is fixed according to the setting on the wireless thermostat.

The wireless thermostat 110 can typically be powered by plugging it into a wall outlet but the smart vent 120 is often away from power outlets and it needs a source of energy to operate the motorized vent and to receive radio signals from the wireless thermostat 110. The source of energy can be batteries or a power cord connected to a wall outlet. Power cord connection is cumbersome since there may not be a wall outlet right near the vent. Batteries will work but they need to be replaced or recharged. This adds cost and inconvenience.

Accordingly, the smart vent 120 uses a thermoelectric generator (TEG) device and circuitry that takes advantage of the temperature difference between the “front” and the “behind” of the vent and converts this temperature difference, DT, to electricity.

When the vent is closed, but a forced air heater is working and forcing warm air through ducts in building, the temperature Duct side (“behind” the vent) will rise while the temperature in the room side of the vent (which is the same as the room temperature) will be lower than Duct side and, with no hot air flowing into the room, will drop gradually. This DT between the Duct side and the Room side is used by the TEG to charge a battery or a capacitor. Once the thermostat 110 in the room drops to a set temperature, it will automatically send a wireless signal to the smart vent 120 to open. Once the vent is opened, the TEG will no longer see a Delta T and will not harvest energy until the thermostat orders the vent to close again. Also note that the system 100 will work in the inverse with cold forced air instead of warm or hot air.

This system 100 is simple to install. One just plugs in the wireless thermostat to a wall outlet away from the vent 120 and removes the existing vent grill and drops in the smart vent 120 in the duct opening. Then one sets the temperature on the wireless thermostat. There is no need to replace an existing thermostat or change anything else. The system 100 will save energy and provide much more comfort than a conventional system.

In another embodiment, thermostats 110 can be placed in multiple rooms and each send the temperature in each room wirelessly to a main thermostat in the building. Once the main thermostat detects that ALL rooms have reached their desired temperature, it will shut off the blower and wait for a room thermostat 110 to report a drop in temperature enough to turn on the heat again (or a raise for cold air).

In an embodiment, the wireless thermostat 110 can be replaced or augmented by a smart phone 130 that has an ambient temperature sensor and a Bluetooth low energy radio and that could also program all the individual room thermostats for the entire building.

In an embodiment, wired and/or wireless communications can be other than Bluetooth. For example, WiFi, powerline, Zigbee, etc. can be used.

In another embodiment, the wireless thermostat 110 is replaced by an infrared, or other similar, sensor to measure temperature built into the vent eliminating the need for an external thermostat and making it easier to install the vent, having only a single piece of equipment, namely the vent, to be installed. This saves cost and adds simplicity to the design.

In another embodiment, “cold” and “hot” plates of the TEG device are designed such that energy harvesting is possible even when the vent is open. This is accomplished by installing one side of the TEG in the duct allowing it to get hot (cold) by the hot (cold) air flow and keeping the other side of the TEG in an insulated compartment unexposed to the air flow. The insulated section keeps the temperature of one side of the TEG relatively constant allowing for the delta temperature between the plates even when the vent is open and only as long as hot (cold) air flows through the vent. Maintaining this delta temperature allows the TEG to continue harvesting energy thus extending the time energy harvested resulting in a higher amount of energy generated.

In another embodiment, the heat sinks used for the “cold” and “hot” sides of the TEG device are made of two different material one with a low temperature coefficient and other with a high temperature coefficient. The side with material with higher temperature coefficient helps the side of the TEG exposed to the air flow (hot or cold) to change (rise or drop) its temperature faster. The other side, which is insulated from the air flow, uses a material with lower temperature coefficient to help keep its temperature from rising or falling rapidly and therefore extending the time delta T is high enough for energy harvesting. A low temperature coefficient material can be Aluminum and a high temperature coefficient material can be copper for instance.

In another embodiment, the vent communicates to a remote server, or a “cloud”, and the cloud communicates the vent information to a smart thermostat or other smart device, instead of directly communicating with the smart thermostat or smart device through local wireless connections.

In another embodiment, more sensors are added to the vent. This includes a humidity sensor to measure room air humidity and report this information to a cloud or smart phone or other smart device. Another sensor is a pressure sensor that measures air pressure near the vent, inside the duct and reports this to another smart device, such as a smart thermostat to stop the flow of air or to open the vent to prevent air pressure build up in the ducts that can be hazardous (when a predetermined pressure threshold is exceeded).

In another embodiment, a microphone and voice recognition circuits are embedded in the vent to allow the user to control the vent functions by voice commands such as “hotter, colder, on, off”. To save power and complexity, the voice recognition circuit is designed to detect one or two “trigger words”. By uttering the trigger words, the user gets the attention of the vent. The vent turns on voice recognition to full power operation where more words can be recognized.

In another embodiment, an air quality sensor is added to the vent to determine the quality of air in the duct and/or the room to close the vent when a hazardous substance, such as smoke, CO, etc. is detected, to activate an alarm, or to report air quality to a cloud server or other smart device. CO2 measurement can also be used to determine the presence and the number of the people in the room as the amount of CO2 rises with more people exhaling air.

In another embodiment, an optical sensor is used in the vent to determine when people enter or exit the room. This can be used to turn the vent on/off to save energy when no one is in the room. Instead of an optical sensor, an embodiment can use an electric field disturbance detector to detect presence of people or animal in the room.

FIG. 2 is a block diagram illustrating the smart vent 120 of the system 100 of FIG. 1. The smart vent 120 comprises a radio 210 coupled to an antenna 200. In an embodiment, the radio 210 includes a Bluetooth low energy (BLE) radio (e.g., a Nordic semiconductor BLE radio). The radio 210 is coupled to a controller 220 (e.g., a Cortex M0 controller), which processes the received commands which drives a motor 230 for closing or opening the vent.

The smart vent 120 further comprises a thermoelectric generator (TEG) 240 coupled to a power management circuit 260 (e.g., Spansion part number MB39C811), which is coupled to a power storage 260 and the controller 220. The TEG 240 can include a Yamaha GKB10 or other energy harvesting circuit that converts DT to electric voltage. The thermoelectric generator 240 has a heat side and a cool side and insulation is placed there between to maximize a heat differential. One side is placed in the room and the other side within the duct.

The power management circuit 250 converts and conditions the voltage to a DC level. The DC level is applied to the power storage 260, such as a rechargeable battery or high capacity capacitor for storage of electric energy to drive all the circuits of the Smart vent 120. The power management circuit 250 also reads the battery/capacitor voltage for managing the power consumption of the circuits.

In an embodiment, the smart vent 120 can also include an air pressure monitor, air quality monitor, CO2 monitor, and/or optical sensor.

FIG. 3 is a block diagram illustrating the controller 220 of FIG. 2. The controller 220 includes one or more processors 300 and memory 310 coupled to an interconnect 330. The interconnect 330 shown in FIG. 3 is an abstraction that represents any one or more separate physical buses, point to point connections, or both, connected by appropriate bridges, adapters, or controllers. The interconnect 330, therefore, may include, for example, a system bus, a form of Peripheral Component Interconnect (PCI) bus, a HyperTransport or industry standard architecture (ISA) bus, a small computer system interface (SCSI) bus, a universal serial bus (USB), IIC (I2C) bus, or an Institute of Electrical and Electronics Engineers (IEEE) standard 1394 bus, also called “Firewire”, and/or any other suitable form of physical connection.

The processor(s) 300 is/are the central processing unit (CPU) of the controller 220 and, thus, control the overall operation of the controller 220. In certain embodiments, the processor(s) 300 accomplish this by executing software or firmware stored in memory 310. The processor(s) 300 may be, or may include, one or more programmable general-purpose or special-purpose microprocessors, digital signal processors (DSPs), programmable controllers, application specific integrated circuits (ASICs), programmable logic devices (PLDs), or the like, or a combination of such devices.

The memory 310 is or includes the main memory of the controller 220. The memory 310 represents any form of random access memory (RAM), read-only memory (ROM), flash memory, or the like, or a combination of such devices. In use, the memory 310 may contain, among other things, software or firmware code 315 for use in implementing at least some of the techniques introduced herein.

Also connected to the processor(s) 300 through the interconnect 330 is an input/output (I/O) interface 320. The I/O interfaces provides the controller 220 with the ability to communicate with other components in the smart vent 220, such as the radio 210 and the motor 230. In an embodiment, the I/O interface 320 is configured to receive aural data (e.g., voice commands) from a microphone in the vent 120.

FIG. 4 is block diagram illustrating the memory 310 and specifically the software 310. The software includes a thermostat engine 410, a motor engine 420 and a power consumption engine 430. Each of the various engines shown in FIG. 4, while shown as software, can be alternatively implemented in pure hardware (e.g., specially-designed dedicated circuitry such as one or more application-specific integrated circuits (ASICs)), or in programmable circuitry appropriately programmed with software and/or firmware, or in a combination of pure hardware and programmable circuitry.

The thermostat engine 410 receives commands via the radio 210 to open/close the vent. The power consumption engine 430 then determines if there is enough power to act on the received command. If the power consumption engine 430 determines there is enough power, then the motor engine 420 issues a command to the motor 230 to open/close the vent. In other embodiments, the motor engine 420 can also issue commands to open/close the vent based on pressure readings, air quality readings, voice commands, and/or the presence of people within the room. Further, the memory 410 can include logic to interact with the air pressure monitor, air quality monitor, CO2 monitor, microphone or optical sensor.

FIG. 5 is a block diagram illustrating the thermostat 110 of FIG. 1. The wireless Thermostat comprise a radio 540 coupled to an antenna (e.g., a BLE radio), a controller 530 coupled to the radio 540, a temperature sensor 520 coupled to the controller 530, and a few keys 560 for user control of the temperature settings. It also has a display 550 to show the current temperature as well as the target (desired) temperature. The wireless Thermostat 110 can also be programmed remotely using a smart phone 130.

In an embodiment, the radio 540 comprises a Nordic semiconductor BLE radio. The controller 530 includes a Cortex M0 controller. The display 550 may comprise a 7-segment three digit LED or LCD. The temperature sensor 520 includes a thermistor the whole device 110 is powered by being plugged into a wall outlet or battery. Typical transformer and rectifying circuits used for converting AC to DC to power the Thermostat are used.

FIG. 6 is a flowchart illustrating a method 600 of operating the smart vent 120 of FIG. 2. Initially, the vent of the smart vent 120 is closed (610) and the TEG 240 charges (620) the power storage 260. The smart vent's antenna 200 then receives (630) a command to open the vent as there is a temperature differential in the room between a measured temperature and a set temperature. The power consumption engine 430 then determines (640) if there is sufficient power in the power storage 260 to open the vent. If there is, the motor engine 420 issues a command to the motor 230 to open the vent, which causes the motor (650) to open the vent. If there is not, the method 600 returns to the charging (620). The method 600 ends when the temperature differential ends, leading to the TEG 240 ceasing to charge the power storage 260.

Also note that the method 600 can be executed inversely. That is, the initial state may be that the vent is open and the motor 230 closes the vent when the room temperature differential between the set temperature and measured temperate is at or close to zero. The method 600 then awaits a command to open the vent and charges the power storage 260 when the vent is closed.

The techniques introduced above can be implemented by programmable circuitry programmed/configured by software and/or firmware, or entirely by special-purpose circuitry, or by a combination of such forms. Such special-purpose circuitry (if any) can be in the form of, for example, one or more application-specific integrated circuits (ASICs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), etc.

Software or firmware to implement the techniques introduced here may be stored on a machine-readable storage medium and may be executed by one or more general-purpose or special-purpose programmable microprocessors. A “machine-readable medium”, as the term is used herein, includes any mechanism that can store information in a form accessible by a machine (a machine may be, for example, a computer, network device, cellular phone, personal digital assistant (PDA), manufacturing tool, any device with one or more processors, etc.). For example, a machine-accessible medium includes recordable/non-recordable media (e.g., read-only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; flash memory devices; etc.), etc.

The term “logic”, as used herein, means: a) special-purpose hardwired circuitry, such as one or more application-specific integrated circuits (ASICs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), or other similar device(s); b) programmable circuitry programmed with software and/or firmware, such as one or more programmed general-purpose microprocessors, digital signal processors (DSPs) and/or microcontrollers, or other similar device(s); or c) a combination of the forms mentioned in a) and b).

Note that any and all of the embodiments described above can be combined with each other, except to the extent that it may be stated otherwise above or to the extent that any such embodiments might be mutually exclusive in function and/or structure.

Although the present invention has been described with reference to specific exemplary embodiments, it will be recognized that the invention is not limited to the embodiments described, but can be practiced with modification and alteration within the spirit and scope of the appended claims. Accordingly, the specification and drawings are to be regarded in an illustrative sense rather than a restrictive sense. 

What is claimed is:
 1. A method, comprising: charging a power storage using a thermoelectric generator in a vent apparatus based on a temperature differential between a room temperature and a temperature in a duct where the vent apparatus is installed; receiving a command from a device to open the vent apparatus so that air flows from the duct to the room; determining if there is sufficient charge in the power storage to open the vent apparatus; opening the vent apparatus if there is sufficient charge; and cease charging the power storage when the temperature differential is no longer sufficient for the TEG to generate energy.
 2. The method of claim 1, further comprising received a command to close the vent apparatus and closing the vent apparatus.
 3. The method of claim 2, further comprising forcing air through ducts when the vent apparatus is closed.
 4. The method of claim 1, wherein the device sends the wireless command when the device measures a preset temperature.
 5. The method of claim 1, wherein the charging further comprises conditioning and converting voltage from thermoelectric generator to direct current.
 6. The method of claim 1, wherein the thermoelectric generator comprises a heat side and a cool side and wherein insulation is placed there between to maximize a heat differential.
 7. The method of claim 6, wherein the one of the sides is located within an insulated compartment.
 8. The method of claim 6, wherein one of the sides has elements with a higher temperature coefficient than the other side.
 9. The method of claim 6, further comprising placing one side in the room and the other side within the duct.
 10. The method of claim 1, further comprising measuring air pressure within the duct and ceasing the air flow within the duct or opening the vent if the pressure exceeds a predetermined threshold.
 11. The method of claim 1, further comprising measuring an air quality within the duct and closing the vent if the air quality measurement indicates a presence of a hazardous substance.
 12. The method of claim 1, further comprising measuring CO2 within the room and determine the presence of people within the room based on the CO2 measurement.
 13. The method of claim 1, further comprising determining a presence of people within the room and closing the vent if no people are detected.
 14. The method of claim 1, further comprising receiving a voice command and adjusting opening of the vent apparatus according to the command.
 15. An apparatus, comprising: a thermoelectric generator that generates voltage based on a temperature differential between a room temperature and a temperature in a duct where the apparatus is installed; a power storage coupled to the generator, wherein the generator is configured to charge the storage; a radio, coupled to the power storage, configured to receive a wireless command from a device to open a vent so that air flows from the duct to the room; and a processor, coupled to the storage and the radio, configured to determine if there is sufficient charge in the power storage to open the vent apparatus; send a command to a motor to open the vent if there is sufficient charge; and a motor, coupled to the storage and processor, configured to open the vent upon receiving the commend, thereby ceasing charging the power storage as the temperature differential decreases.
 16. The apparatus of claim 15, wherein the radio is further configured to receive a command to close the vent apparatus and the processor is further configured to send a command to the motor to close the vent.
 17. The apparatus of claim 16, further comprising a blower configured to forcing air through the duct when the vent is closed.
 18. The apparatus of claim 15, wherein the device is configured to send the wireless command when the device measures a preset temperature.
 19. The apparatus of claim 15, further comprising a power management circuit, coupled to the generator and storage, configured to condition and convert voltage from the thermoelectric generator to direct current.
 20. The apparatus of claim 15, wherein the thermoelectric generator comprises a heat side and a cool side and insulation is located there between to maximize a heat differential.
 21. The apparatus of claim 20, further comprising an insulated compartment holding one of the sides.
 22. The apparatus of claim 20, wherein one of the sides has elements with a higher temperature coefficient than the other side.
 23. The apparatus of claim 20, wherein one side located within the room and the other side within the duct.
 24. The apparatus of claim 15, further comprising a pressure sensor within the duct and the processor is further configured to send a command to cease the air flow within the duct or open the vent if the pressure exceeds a predetermined threshold.
 25. The apparatus of claim 15, further comprising an air quality sensor and the processor is further configured to send to a command to close the vent if an air quality measurement indicates a presence of a hazardous substance.
 26. The apparatus of claim 14, further comprising a CO2 sensor and wherein the processor is configured to determine the presence of people within the room based on a CO2 measurement.
 27. The apparatus of claim 14, further comprising an optical sensor configured to determine a presence of people within the room and wherein the process is further configured to send a command to close the vent if no people are detected.
 28. The apparatus of claim 15, further comprising a microphone configured to receive voice commands and the processor is further configured to send to a command to adjust opening of the vent based on the received command. 